Some beverage containers such as cups that are used by an infant or the like in drinking a beverage include a lid disposed on the container and a straw disposed in the lid. Such a straw and beverage container has the advantage of allowing an infant or the like to practice drinking a beverage in the container using the straw. Thus, many parents such as mothers use such a straw and beverage container.
The straw and beverage container includes an outer lid formed thereon and disposed to block and cover the straw so that a parent or the like can carry the beverage container with a beverage contained inside and with the straw installed therein.
However, when the parent carries the straw and beverage container with hot milk or the like contained inside and with the outer lid closed, the pressure in the container increases, leading to a difference between the pressure in the container and atmospheric pressure. Thus, when the parent opens the outer lid at a destination or the like to unblock the straw, for example, the hot milk or the like in the container may disadvantageously squirt through the straw.
Thus, a vent hole or the like which is in communication with the space in the container is conventionally formed in the lid of the beverage container to prevent, for example, a possible squirt of the beverage in the container such as milk through the straw or the like.
On the other hand, the presence of such a vent disadvantageously causes the beverage in the container to leak when the parent or the like carries the straw and beverage container in a bag or the like.
Thus, proposals have been made for a vent hole with a valve structure and a configuration in which the vent hole is allowed to perform a ventilation operation when the outer lid is opened. Furthermore, a proposal has been made to block the vent hole when the straw and beverage container is carried or when an infant or the like holds the straw in the infant's mouth and drinks the beverage in the beverage container (for example, Patent Literature 1).